1. Field of the Invention
The present invention relates to an image forming apparatus using an electrophotographic printing technology applicable to a facsimile, a printer, a copier, and a multifunction product having these functions, and particularly relates to an image forming apparatus including an optical neutralizing device positioned close to a photosensitive body and a cleaning unit.
2. Description of the Related Art
An image forming apparatus using an electrophotographic printing technology includes a charging unit, an exposure unit, a developing unit, a transfer unit, a neutralizing unit, a cleaning unit, and other units that are arranged around a photosensitive body as an image carrier. The surface of the photosensitive body is uniformly charged by corona discharge or the like, and is exposed to light corresponding to characters or the like to be printed to form an electrostatic latent image, and the image is developed with toner. Subsequently, the toner on the photosensitive body is transferred onto an intermediate transfer belt by bringing the intermediate transfer belt in contact with the toner image and by applying bias. The toner on the intermediate transfer belt is transferred onto the paper, and the toner image is fixed by heating, or heating and pressurizing the paper on which the toner is transferred to complete printing. After the completion of the transfer, the surface of the photosensitive body is cleaned and neutralized, and similar processes are further repeated.
As an image forming apparatus having the structure as described above, Japanese Patent No. 3234839 discloses a structure in which a neutralizing lamp (erasing lamp) is arranged at a position close to a photosensitive body and a cleaning unit. The neutralizing lamp is fixed on a bracket integrated with the image forming apparatus main body. The neutralizing lamp does not generally require maintenance substantially until the end of the service life of the main body. Therefore, typically, a neutralizing lamp is integrally installed in the image forming apparatus main body in such a structure that the neutralizing lamp cannot be inserted and removed as disclosed in Japanese Patent No. 3234839.
On the contrary, a photosensitive body, an intermediate transfer belt, and a cleaning unit that are positioned close to a neutralizing lamp require periodic maintenance and thus need to have a structure readily detachable from an image forming apparatus main body. However, the units may be, damaged by the contact with the neutralizing lamp, a sheet metal bracket fixing the neutralizing lamp, or the like during their insertion and removal because the neutralizing lamp is closely arranged. Accordingly, consideration is required to design a layout for preventing such breakage and for enabling units to be readily replaced. Specifically, in recent years, image forming apparatuses are designed to have a layout in which components are arranged extremely close to each other in the main body in order to save space. However, for easy replacement, the layout is required to have a structure with which general users can replace the components without any particular concern.